Improved roofing-compound



annex sans pawn can,

JOSEPH V. DOUGLAS, OF PHILADELPHIA, PENNSYLVANIA, ASSIGNOR TO HIMSELFAND JAMES A.'oRAIe, or SAME PLACE.

Letters Patent No. 107,232, dated September 13, 1870.

iMPROVED ROOIING-I ZOMPOU'N D.

the Schedule referred to in these Letters Patent and'making part of thesame To all whom it may concern Be it known that I, Josnrn V. DOUGLAS,of the city and county of Philadelphia and State of Pennsylvania, haveinvented'a new and improved Roofing- Oomposition andI do hereby declarethat the following is a full,clear, and exact description. of the same.

My inventionrelates to preparations for making a water-proof roof, andconsists in a compound formed of iron scales, which are producedprincipally in rolling-mills by the combined action of heat andpressure, and united to such a proportion of tar, or other waterrepellant, as will firmly connect and cohere said scales, and produce auniform and homogeneous coating over the roof. These scales possess twopeculiar characteristics not observable in filings, turnings, or

other waste. of iron,,namely, that theyare nearly unoxydizable bymoisture, and require a much higher degree of temperature to melt themthan other ir'on oflal.

The scales and tar may be oonjointly employed in any suitable way, as myinvention does not consist in the manner of applying this c0mponnd,"butin the thing itself, however applied.

The mode which I preferably employ, at the present .t-ime, is to mix thescales intimately with hot liquid tar. and apply it directly to the roofin one' or more coats, as may seem desirable. The scale will naturallyfall into place and exhibit an incline corresponding to the pitch of theroof.

Iron borings, turnings, filings, and pulverized ore have been employedand patented heretofore in-combination with various other ingredients,but they lack the form and peculiar adaptation to the purpose in view,which is possessed by the principal article in my compound. r I

The first three curl up; have a tendency to stand erect on theirtransverse edges,'and cannot be made to lie smooth upon the facev of theroof. This constitutes a very serious objection to them. Under thesecircumstances, they form slight ridges in which the water rests, and isafl'o'rded an opportunity to work through. The ground ore is granulated,and, conse: quently, open to the same objection as sand, namely,

that it will be gradually washed .out bythe operation of heavy rains,while the atoms or pieces do not present a continuous slope to shed thewater. v

These rolled scales are so condensed by heavy pressure as to have a highspecific gravity, and to He in sheets like slate or shingles. The wateris thus enabled to pass freely without any obstruction over the smoothsurface formech Having thus described all that is necessary to a clearunderstanding of my invention,

\Vhat I claim as new, and desire toprotect by Letters Patent, is:-

-A surface coating for roofs, formed of rolled iron 1 scales, applied inhot liquid tar and in one or more successive coats, as set forth.

- JOSEPH V. DOUGLAS.

\Vitnesse's .ALnx. Convnmn, B. F. JARRETT.

